An example of using Websocket developed by Python

Posted by starmikky on Fri, 17 Jan 2020 15:14:10 +0100

I learned how to implement web development in java. Today I want to try to implement it in python, so I found the code on the Internet

2.1. Effect 1 (a client connects to the service and sends a message)

2.2. Effect 2 (another client connects to the service and sends a message)

2.3. Effect 3 (the service receives all messages from the client and returns messages)

2.4. Effect 4 (dropping one client does not affect other socket connections)

2.5. Effect 5 (list all connected client objects and client objects currently sending messages)

3. Core code

#! -*- coding: utf-8 -*-
Author: ZhenYuSha
Create Time: 2019-1-14
Info: Websocket Use example of
import asyncio
import websockets

websocket_users = set()

# Check the client's permission. The user name and password can exit the cycle only after passing
async def check_user_permit(websocket):
    print("new websocket_users:", websocket)
    print("websocket_users list:", websocket_users)
    while True:
        recv_str = await websocket.recv()
        cred_dict = recv_str.split(":")
        if cred_dict[0] == "admin" and cred_dict[1] == "123456":
            response_str = "Congratulation, you have connect with server..."
            await websocket.send(response_str)
            print("Password is ok...")
            return True
            response_str = "Sorry, please input the username or password..."
            print("Password is wrong...")
            await websocket.send(response_str)

# Receive the client message and process it. Here, simply return the message sent by the client
async def recv_user_msg(websocket):
    while True:
        recv_text = await websocket.recv()
        print("recv_text:", websocket.pong, recv_text)
        response_text = f"Server return: {recv_text}"
        print("response_text:", response_text)
        await websocket.send(response_text)

# Server side main logic
async def run(websocket, path):
    while True:
            await check_user_permit(websocket)
            await recv_user_msg(websocket)
        except websockets.ConnectionClosed:
            print("ConnectionClosed...", path)    # Link disconnect
            print("websocket_users old:", websocket_users)
            print("websocket_users new:", websocket_users)
        except websockets.InvalidState:
            print("InvalidState...")    # invalid state
        except Exception as e:
            print("Exception:", e)

if __name__ == '__main__':
    print(" websocket...")
    asyncio.get_event_loop().run_until_complete(websockets.serve(run, "", 8181))


        var socket;
        if ("WebSocket" in window) {
            var ws = new WebSocket("ws://");
            socket = ws;
            ws.onopen = function() {
                console.log('Successful connection');
                alert("Successful connection, Please enter your account and password");
            ws.onmessage = function(evt) {
                var received_msg =;
            ws.onclose = function() {
        } else {
            alert("Browser does not support WebSocket");
        function sendMeg(){
            var message=document.getElementById("name").value+":"+document.getElementById("mes").value;

4. Github source sharing

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Topics: socket Python github Web Development